Erlotinib,a kind of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs),has been effectively used in the treatment of non-small cell lung cancer (NSCLC).Although it prolongs patients survival time,erlotinib is limited to be further applied for its resistance.It has been proved that threonine to methionine mutations in codon 790 (T790M),Kirsten rat sarcoma viral oncogene homolog (KRAS) mutation and the amplification of met oncogene play important roles in the drug resistance.Based on the different molecular mechanisms of resistance,multiple clinical trials of the second generation TKIs,retreatment of chemotherapy or erlotinib and subsequent treatment according to failure modes have been developed.

4. 0 Log was precede 5 DBS samples whose plasma VL

ObjectiveTo establish a novel assay for HIV-1 p24 ultrasensitive detection based on Gold Nanoparticle Probe (GNP) and PCR.MethodsSandwich ELISA method was established by a pair of anti-p24 monoclonal antibodies (mAbs),1G12 and 1D4,and was used to detect recombinant HIV-1 p24 antigen.The bio-barcode DNA was 47 bp,selected from genome of Arabidopsis,and formed double-stranded DNA by hybridization with the capture DNA (complementary with bio-barcode DNA) modified with sulfhydryl.Then double-stranded DNA were conjugated on the surface of 1D4-modified gold nanoparticles by sulfhydryl,and the Gold Nanoparticle Probe was produced.1G12 was precoated in the micropaltes,and in the presence of target recombinant HIV-1 p24 protein,a sandwich immuno-complex would form by adding GNP.Then the bio-barcode DNA in the immuno-complex were released by heating as detection signal,and consequently characterized by the polymerase chain reaction (PCR) with synthesized special primers and analyzed by 4％ agar gel electrophoresis,so HIV-1 p24 antigen could be evaluated.The sensitivity comparison between the new assay and ELISA can be done.ResultsSandwich ELISA was used to quantify HIV-1 p24 antigen by monoclonal antibodies 1G12 and 1D4,and the limit of detection (LOD) was 1000 pg/ml.The new GNP assay was established by the same pair of antibodies,combined with PCR and agar gel electrophoresis,and was used to indirectly detect HIV-1 p24 antigen.The band intensity of PCR products paralleled with the quantity of HIV-1 p24 antigen,and the limit of detection (LOD) could reach down to 1 pg/ml.ConclusionThe new assay based on GNP and PCR was efficient in the detection of HIV-1 p24,which is at least 3 orders of magnitude more sensitive than traditional ELISA.

OBJECTIVETo study the correlation between the MRI apparent diffusion coefficient (ADC) value and histological grade and molecular biology of breast invasive ductal carcinoma (IDC).

METHODSThis retrospective study included 125 patients with IDC verified by pathology from February 2010 to February 2013. Conventional MRI and diffusion-weighted imaging (DWI) examination were performed using a 3.0T scanner with diffusion factor of 0 and 800 s/mm(2). The region of interest (ROI) was drawn on the largest lesion and/or its two adjacent slices. The ADC value of the whole tumor was calculated as the mean ADC value. The correlation between mean ADCs and histological grade and biological factors was analyzed.

RESULTSThe mean ADC of pathological grade I, II and III IDC was (1.152 ± 0.072)×10(-3) mm(2)/s, (1.102 ± 0.101)×10(-3) mm(2)/s, and (1.035 ± 0.107)×10(-3) mm(2)/s, respectively. There was a statistically significant difference among them (P = 0.003). Statistically a significant difference was observed between grade III and I (P = 0.034), grade III and II (P = 0.006), but not between grade I and II (P = 0.741). A significant correlation was observed between ADC value and pathological grade (r = -0.342, P < 0.001). The median ADC values were significantly higher in the ER-negative than in the ER-positive cases [(1.130 ± 0.115)×10(-3) mm(2)/s vs. (1.060 ± 0.089) ×10(-3) mm(2)/s, P < 0.001)], in PR-negative than in PR-positive cases [(1.121 ± 0.106)×10(-3) mm(2)/s vs. (1.055 ± 0.096) ×10(-3) mm(2)/s, P < 0.001)], and in Ki-67-negative than in Ki-67-positive cases [(1.153 ± 0.090)×10(-3) mm(2)/s vs. (1.063 ± 0.101) ×10(-3) mm(2)/s, P < 0.001]. A statistically significant correlation was observed between ADC value and expressions of ER, PR, and Ki-67 (r = -0.311, r = -0.317, r = -0.414, P < 0.001).

CONCLUSIONADC value of breast invasive ductal carcinoma is correlated with histological grade, and expression of ER, PR and Ki-67.

Breast Neoplasms ; diagnosis ; Carcinoma, Ductal ; diagnosis ; Diffusion Magnetic Resonance Imaging ; Humans ; Magnetic Resonance Imaging ; Retrospective Studies

OBJECTIVEAn approach for analysis of HIV quasispecies using Miseq high-throughput sequencing platform (hereinafter referred to as Miseq platform) was established and applied to contact tracing for a possible case of HIV sexual transmission.

METHODSFour plasma specimens were collected from 2 HIV infections (P1 and P2) suspected to be involved in the sexual transmission and 2 local HIV infections as controls (P3 and P4). The RNAs were extracted from the specimens and then reverse-transcribed into cDNA. After HIV subtyping, Miseq platform was performed to detect and sequence the HIV quasispecies (352 bp) in each specimen. The frequency of quasispecies was counted and ranked. Intrapersonal and interpersonal genetic distance and phylogenetic tree were calculated by using the top 5, 20, 100, 500, and all quasispecies, respectively.

RESULTSThe subtypes of HIV from all 4 specimens were CRF01_AE. 23 788 to 37 397 cleaned sequences representing 1 229 to 1 412 unique HIV quasispecies were obtained from these specimens by using Miseq platform. The average genetic distance (3.5%-4.5%) between quasispecies from specimens P2 and P1 was significantly lower than that (10.3%-19.6%) between quasispecies from P2 and the controls (P3 or P4). Phylogenetic tree analysis indicated that sequences from specimens P1 and P2 clustered together while sequences from P3 and P4 exhibited completely independent clusters. When the top 20 or more quasispecies from each specimen were analyzed, sequences from P1 showed a paraphyletic relationship with those from P2, which may indicated that the direction of HIV transmission was from P1 to P2.

CONCLUSIONWith the feature of convenient and economic operation, Miseq platform has high practical value in contact tracing of possible HIV transmission.

Contact Tracing ; HIV Infections ; HIV Seropositivity ; HIV-1 ; Humans ; Phylogeny

Objective To compare the bio-equivalence among commercial HIV-1 viral load tests,including EasyQ HIV-1 v2.0 (EasyQ) from bioMerieux NucliSens of France;VERSANT HIV-1 RNA 3.0 assay (bDNA) from Siemens Healthcare Diagnostics of USA;COBAS AmpliPrep/COBAS TaqMan HIV-1 test (Taqman) from Roche Molecular Diagnosis of USA;Abbott Real Time HIV-1 Kit (M2000) from Abbott Molecular of USA and two domestic HIV-1 viral load test kits (domestic kit) from DaAn Gene Company of Sun Yat-Sen University and Liaoning Bio-Pharmaceutical company of Northeast pharmaceutical group,by using proficiency test results in China from 2013 to 2015.Methods A total of 2 954 proficiency test results,obtained from 22 positive samples of 6 proficiency tests in 155 laboratories conducted by China CDC were analyzed during 2013-2015.The results from each sample were first logarithmic transformed and then grouped according to the method used,the mean value of logarithmic results was calculated.Subsequently,22 clusters of mean values were analyzed by Bland-Altman analysis for the consistency,and linear regression analysis for the interdependency.Results The results indicated that,by taking Taqman as the reference,EasyQ,M2000,bDNA and domestic kit had good consistency (90％-100％) and interdependency.Conclusion All the viral load tests were bio-equivalent.Moreover,according to the conversion formula derived from domestic proficiency test results,all the viral load results could be converted,which is critical for epidemiological analysis.